I am running PSS 275/30/19 on a 10" wheel with a 20 ET in the back of an E90 with a KW V3 lowered to 13.5" from the center of the roundel to the fender. No rubbing. Knowing what I know now about tires I would have gotten the 275/35/19. My fronts are 245/35/19 on an 8.5" w/15 ET. I'm planning on running the same fronts with 285/30/19 if they ever come out.

I have PSS 275/35/19 on the rear with stock 9.5" wheels and stock ride height, and I rubbed badly with a 15mm spacer. I got away with a 12mm on 265s, but not 15mm on 275s. And I'm running -2.0 camber, too.